English This entry needs a photograph or drawing for illustration. Please try to find a suitable image on Wikimedia Commons or upload one there yourself! Etymology From breast + rail. Noun breastrail (plural breastrails) The upper rail of a parapet of ordinary height, such as of a balcony, the railing of a boat, etc. References “breastrail”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC. Anagrams Baltierras, arbalisterWikiwand - on Seamless Wikipedia browsing. On steroids.